Is there a way in Firefox Quantum to make the New Tab (+), Space (painted in green) ,Minimize, Maximize / Restore, and Close buttons that can be found on the right side of the Title Bar (marked in red) , to float or if not at least disappear ? (The space is obviously redundant)

In the pre-Quantum versions I had a great extension called "Hide Caption Titlebar Plus" which did the trick unfortunately it became a legacy extension with no suitable replacement.
Thank you